In many cases, products are subjected to a quality control after their production to be able to detect possible flaws. Various methods and devices are known here in the prior art precisely for checking surfaces and connections between components, which usually use multiple cameras for the examination. For example, soldered joints are checked in that a camera records a soldered object and makes a decision in regard to the quality of the soldered joint via a corresponding analysis program on a computer. A corresponding method and a device are described in DE 10 2004 004 278 A1. In addition to the camera, a handling device is provided therein to move the soldered object in relation to the stationary camera. The handling device grips the circuit board to be evaluated and rotates it appropriately in front of the camera.
The use of a recording unit for three-dimensional images for executing line scanning in an equipping device for electronic components for automatically equipping circuit boards with electronic components is known from DE 697 10 714 T2. Displacement of the recording unit in the x and y directions over the circuit board to be equipped is provided for this purpose.
A device and a method for automatically inspecting moving surfaces is known from DE 697 03 487 T2. Three different illumination/observation channels are used for this purpose.
Furthermore, methods and devices for checking bottles having a threaded section are known from DE 696 10 925 T2, for example. In these methods, the bottles move along a high-speed line, video images being recorded of each bottle, the pixels of the particular video image being processed, and the pixels being examined in interesting areas of interest, which were previously selected, to detect thread defects in general over the circumference of the bottle.
DE 203 17 095 U1 discloses a device for recognizing flaws of an object surface in cast parts in particular, a light source for illuminating the object, a light detector for recording a beam reflected from the object surface toward the illumination beam, and an analysis unit for analyzing the image data thus received for error recognition being provided. In the analysis, the number of pixels to be examined and the size of the pixel regions to be considered are to be kept as small as possible. Among all recorded pixels, those whose brightness values deviate from a mean pixel brightness by more than a predefinable tolerance value are ascertained.
The use of a laser beam for scanning a circuit board for its examination is also known, e.g., from DE 198 83 004 T1, in which the scanning device comprises two galvanic mirrors having rotating shafts orthogonal to one another and a scanning lens.
The use of six cameras for quality checking in wafers is disclosed in DE 103 52 936 A1, two camera systems being oriented vertically from above on the upper edge zone of the wafer, two camera systems being oriented from below on the lower edge zone, and two camera systems being oriented horizontally on the lateral edge of the wafer. Defects are detected using automatic classification.
DE 101 04 355 A1 discloses a device and a method for image scanning of the surface of an object, for use in a lacquering line for determining contaminants and/or flaws of the surfaces of an object. The device comprises a recording system and a controllable transport medium, the transport medium being able to be moved linearly along a horizontal axis in relation to the recording system and the recording system being able to be moved along a second vertical axis using a travel medium. The recording system comprises a camera and a light.
The devices and methods of the prior art described above each have the disadvantage that the achievable precision of the recorded information is not especially high and the speed of the image recording is also quite low. Critical image recording in particular, as when reading out codes on circuit boards which are positioned at different points, is not possible using these devices of the prior art.